Return-line vacuum pump for steam-heating systems



B. SKIDMOFQE, JR

2 Sheets-Sheet l l RETURN LINE VACUUM PUMP FOR STEAM HEATING SYSTEMSAug? 5 w24., www@ B. SKIDMORE, JR

RETURN LINE VACUUM PUMP FOR STEAM HEATING SYSTEMS Filed Dec. 1o, 1921 2shwrs-sheer 2 Patented Aug. 5, 1924.

T E S BENJAMIN SKIDMO'RE, J R., 0F CHICAGO, ILLINOIS.

RETURN-LINE VACUUM PUMP FOR STEAM-HEATING SYSTEMS.

Application led December 10, 1921.

To all whom t may concern.'

Be it known that I, BENJAMIN SKIDMORE, J r., a citizen of the UnitedStates, residing at Chicago, in the county of Cool: and State ofIllinois, have invented certain new and useful Improvements inReturn-Line Vacuum Pumps for Steam-Heating Systems, of which thefollowing is a specification.

This invention relates to improvements in return line vacuum pumps,particularly adapted, though not necessarily limited in its use, insteam heating systems, and one of the objects of the invention is toprovide an improved apparatus of this character for maintaining a vacuumon the steam line system and for returning the condensation back to theboiler.

A further object is to provide an improved apparatus of this characterin which the air and condensates are handled through the same rotor, theair being separated from the liquid before the latter is returned to theboiler.

To the attainment of these ends and the accomplishment of other new anduseful objects as will appear the invention consists in the features ofnovelty in substantially the construction, combination and arrangementof the several parts, hereinafter more fully described and claimed andShown in the accompanying drawings illustrating this invention and inwhich Figure 1 is a vertical, longitudinal sectional view.

Figure 2 is a rear elevation of Figure 1.

Figure 3 is a detail vertical, sectional view taken on line 3-3, Figurel.

Referring more particularly to the drawings the numeral 10 designatesgenerally a casing having an inlet opening 1l for liquid and a dischargeoutlet opening 12.

Within the casing is a rotor 13 which is connected with the shaft 14 forrotation therewith and this shaft 14 extends through the casing and fora considerable distance on each side thereof. Connected with the casingis a support 15 through which one end of the shaft 14 passes and thissupport is provided with a suitable stuffing box 16, grease grooves 17,and a ball bearing 18. To the other side of the casing is connectedanother support 19 having a stutling bx 20, grease grooves 21, and aball bearing 22 for the shaft.

The casing is constructed to form a rotor chamber 23 and an inletpassage 24 which Serial No. 521,334.

has communication with the inlet opening 11 and communicates with therotor chamber 23, preferably adjacent the axis of rotation of the shaft14, as at 25. Arranged within the rotor chamber and encompassing. theshaft is a stationary element or post 26, which is hollow to formpassages 27 having outlets 28. These passages 27 have communication asat 29 with a passageway 30, preferably in the casing wall and whichpassageway 30 has an inlet opening 31, with which latter the return linepipe of the system is connected so that the fluid and liquid which isreturned from the system will be delivered through the opening 31 intothevpassage 30, and from there into the passages 27, to be dischargedthrough the outlet 28.

A portion of the rotor 13 encompasses the element 26 and the rotor is ofa construction similar to that disclosed in my United States Patent No.1,390,390, issued September 13, 1921. The rotor is preferably of adouble construction, that is it is provided with blades on each sidethereof. Two blades are` preferably provided on each side, the inner endof each blade overlapping the inner end of the next adjacent blades. Theblades are suitably spaced from each other and the ends or portions32-33 and 34-35 of the respective blades' are arranged substantiallyconcentric with the axis of the rotor, while the portions 36-37 of therespective blades are arranged spirally about the axis of the rotor, sothat the blades as they are advanced will' move into the liquid to takeup a portion thereof. The portion of the liquid thus taken up will beconfined in the passages between the blades and will remain in asubstantially quiescent condition, with the result that as the rotor isactuated the walls of the passage will advance with respect to theliquid confined in the passage and there will be little centrifugalforce or turbine action imparted to the liquid, while at the same timethe liquid will have a slight radial flow to be replaced by othersupplies between the walls of the passage. This is due to the fact thatthe blades are arranged substantially parallel, are rotated at a veryhigh rate of speed and are concentric with the axis of the rotor.

The blades on one side of the rotor are so arranged with respect t0 theblades on the opposite side that the parallel portions of the walls ofthe passages on one side will be intermediate the parallel portions ofthe walls of the passages on the other side. This construction isdesirable and advantageous in that the rotor will be balanced thereby.

Durin the operation of the rotor, the inlets o the respect-ive passagesbetween the blades will pass the outlet openings 28 of the passages 27in the element 26, with the result that as the blades advance they willgradually close and open the outlets 28 and slugs of air or Huid will betaken into the passages between the blades alternately with slugs ofliquid, and as the blades first cut into and are advanced with respectto the liquid, the liquid will be discharged through the outlet opening12 of the cas ing and into a closed tank 38, which latter is providedwith an outlet opening 39 for the air or iuid. y

This tank may be of any desired size and configuration and is preferablyprovided with a'baiiie or detlector 40, arranged adjacent but spacedabove the bottom of the tank. This baiile extends across the inletopening 41 with which the outlet opening 12 communicates so that theliquid and Huid which is directed into the tank through the inlet 41will be delivered at one end of the tank so as to provide a sufficienttime to permit the air and gases to be separated from the liquid as theyHow from one end of the tank to the other end thereof. The air and gaseswill rise to the top of the tank and will be discharged through theoutlet opening 39, if the latter is open.

The opening 39 is provided with a valve seat 42 with which a valve 43co-operates. The valve 43 is itself provided with a valve openingtherethrough and a valve seat 44 with which a supplemental valve 45co-operates. This supplemental valve as well as the valve 43 is adaptedto be controlled by means of a suitable float 46 which is connected witha lever 47, pivotally mounted as at 48. The valve 45 is provided with astem 49 which passes through a suitable opening in the lever 47 andcotter pins 50 are provided through the stem 49 on each side of thelever 47 so that the rising and falling movement of the float 46 willshift the valve 45.

With this construction it will be manifest that when the liquid level inthe tank 38 is sulicient to permit the float 46 to drop, the lever 47will unseat the valve 45 and this unseating of the valve 45 will relievethe pressure in the tank 38 sufficiently to permit the valve43 to open.When the float 46 rises the valve 45 will first be seated upon its seat44 and the valve 43 will then be seated upon its seat 42 to close theoutlet 39.

The tank 38 is also provided with an outlet opening 51 through thebottom thereof, which communicates with the inlet opening 11 of thepassages 24 so that liquid from the tank 38 will be supplied to therotor through the opening 25.

As the rotor 13 rotates the inlets of the passages between the blades ofthe rotor will pick up the liquid which is being delivered into theopening 25.

The bottom of the tank 38 is also provided with another liquid outletopening 52 which has communication with the passage 53, the latter beingpreferably arranged within the casing 10. This passage 53 delivers theliquid from the tank to a centrifugal pump device 54, which is alsoconnected with the shaft 14 for rotation therewith. This centrifugalpump device 54 operates in a casing 55, into which it discharges theliquid received through the inlet 56 and from the casing 55 the liquidis discharged through an outlet passage 57 back into the boiler.

Arranged within the tank 38 is an upright tubular member 58 whichencompasses the outlet opening 52 and this upright 58 extends throughthe partition or baiie 40 and is of any desired height so as to causethe liquid to accumulate in the tank 38 before it isdischarged. Ifdesired a tubular member 59 may also be provided within thetank toencompass the member 58 and is spaced therefrom. This tubular member 59is provided with inlet openings 60 adjacent the bottom thereof so thatthe liquid in the tank issupplied to the tubular member 58 through thebottom of the tubular member 59.

A partition 61 is preferably arranged intermediate the partition orbatlie 40 and the bottom of the tank and between the inlet and outletpassages 11 and 12 so as to induce a circulation of the liquid throughthe tank and to prevent the liquid from flowing directly from theopening 12 through the opening 11.

In operation the rotor 13 will create a suction from the return linethrough the opening 31 and the air and condensates which are drawnthrough the openin 31 by the rotor will be delivered with 2(liquid fromthe tank 38 back into the tank through the opening 12. The baiiie 40will cause the liquid and gases to circulate toward one end of the tankand the air and gases will be separated from the liquid and the air willrise to the top of the tank. lf the outlet 39 is open the air lwill passtherethrough but when the liquid in the tank rises sufficiently high tocause the float 46 to close the outlet 39 the air will accumulate at thetop of the tank. The liquid from the tank will How through the opening51 into the passage 24, through the opening 11, and will be delivered tothe rotor 13, the rotor operating to cause a circulation of the liquidfrom liquid level in the tank 38 drops below the top of the pipe 58. I.

The operation of the rotor 13 will cause the condensates to be deliveredinto the passages 30 and they will then be delivered by the rotor withthe liquid which is supplied to the rotor through the opening 25, to thetank 38.

If the liquid which is thus supplied to the tank is a greater quantitythan can be handled under normal conditions, by the centrifugal pump 54,then the liquid as it fills the tank will cause the float 46 to rise andthis will close the outlet opening 39, with the result that pressurewill be built up in the tank 38.

As the pressure is built up or increased in the tank 38 by the rotor 13there will be increased pressure upon the liquid delivered from the tankto the centrifugal pump 51 and this will cause the centrifugal pump todeliver the liquid back to the boiler or receiver against a greater heador pressure, or Will cause the centrifugal pump to deliver a largervolume of liquid to the receiver or boiler.

The liquid being delivered to the tank 38 through the opening 12, passesunder the baffle or deflector 40, Which latter together with the bottomof the tank forms a passageway for the liquid and air and as this)assageway is somewhat extended there will lie a greater interval oftime for the liquid and air to flow up into the tank than would beconsumed in the event that the baille 40 is omitted, therefore a morecomplete separation of the air from the liquid will be effected. f

By the building up of the pressure in the tank by the rotor 13 s0 thatthe liquid will be supplied to the centrifugal pump 5l under anincreased pressure, it will be manifest that the rotor 13 acts as abooster for the centrifugal pump, or in other words the rotor andcentrifugal pump operate as a two stage pump.

Obviously the valve for controlling the air outlet 39, also serves thepurpose of preventing the escape or loss of any of the condensatesthrough the opening.

l/Vhile the preferred form of the invention has been herein shown anddescribed it is to be understood that various changes may be made in thedetails of construction and in the combination and arrangement of theseveral parts, within the scope of the claims, without departing fromthe spirit of this invention.

lVhat is claimed as neuT is:

1. In combination, a closed tank for receiving air and water and havingan air outlet, a rolo'r casing having an outlet discharging into thetank and an inlet leading from the tank, a rotor in the casing, meansfor actuating the rotor, said rotor operating tao. circulate liquid fromthe tank through l e casing and back into the tank, there being aconduit for air and water and having an outlet adjacent the path ofmovement of the rotor and in which conduit a suction is created by therelative movement of the rotor and liquid, there being a liquiddischarge outlet leading from the tank, and means operatingautomatically to control the air outlet, the said rotor also operatingto build up pressure in the tank whereby the liquid will be deliveredfrom the tank through the said discharge outlet under pressure.

2. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and in Which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from thel tank, and means controlled by the liquid level in thetank forcontrolling the said air outlet, the said rotor also operatingto build up pressure in the tank whereby the liquid will be deliveredfrom the tank through the said discharge outlet under pressure.

3. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet disllO charging into thetank and an inlet leading from the tank, a rotor in the casing means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, a double valve for controlling the air outlet,and a lioat for controlling the valves, one of the valves being adaptedto be unseated While the other valve remains seated, the

said rotor operating when the valves are seated to build up pressure inthe tank whereby the liquid will be delivered from the tank through thesaid discharge outlet under pressure.

4. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and'in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, means operating automatically to control the airoutlet, the said rotor also operating to build up pressure in the tankwhereby the liquid will be delivered from the tank through the saiddischarge outlet under pressure, and a pump, the inlet of the pump beingconnected with the liquid discharge outlet from the tank.

5. In combination, a closed tank for receiving air and Water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, mea-ns operatingl automatically to control theair outlet, the said rotor also operating to build up pressure in thetank whereby the liquid will be delivered from the tank through the saiddischarge outlet under pressure, and a pump operating in unison with therotor, the inlet of the pump being connected with the liquid dischargeoutlet from i the tank.

6. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, means operating automatically to control the air7. In combination, a closed tank for rev ceiving air and water andhaving an air outlet, a rotor casing having an outlet discharging intothe tank and an inlet leading from the tank, a rotor in the casing,means for actuating the rotor, said rotor operating to circulate liquidfrom the tank through the casing and back into the tank, there being aconduit for air and water and having an outlet adjacent the path ofmovement of the rotor and in which conduit a suction is created by therelative movement of the rotor and liquid, means within the tank forinducing a circulation of the liquid to permit a separation of the fluidtherefrom, there being a liquid discharge outlet leading from the tank,and means operating automatically to control the air outlet, the saidrotor also operating to build up pressure in the tank whereby the liquidwill be delivered from the tank through the said discharge outlet underpressure.

8. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and Water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, means operating automatically to control the airoutlet, the said rotor also operating to build up pressure in the tankwhereby the liquid will be delivered from the tank through the saiddischarge outlet under pressure,'and a pump operating in unison with therotor, the inlet of the pump being connected with the discharge outletfrom the tank, the inlet of the rotor and the inlet of the pump beingboth disposed intermediate the rotor and-pump.

9. In combination, a closed tank for receiving air and water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, and means operating automatically to prevent theescape of condensates from the tank through the said air outlet.

l0. In combination, a closed tank for receiving air and Water and havingan air outlet, a rotor casing having an outlet discharging into the tankand an inlet leading from the tank, a rotor in the casing, means foractuating the rotor, said rotor operating to circulate liquid from thetank through the casing and back into the tank, there being a conduitfor air and Water and having an outlet adjacent the path of movement ofthe rotor and in which conduit a suction is created by the relativemovement of the rotor and liquid, there being a liquid discharge outletleading from the tank, a centrifugal pump, the inlet of which is in opencommunication with the outlet from the tank, and means for causing therotor and centrifugal pump to operate as a two-stage pump, the lastrecited means embodying valve mechanism for controlling the air outlet.

11. A closed tank for receiving air and liquid, a rotor operating tocirculate the liquid from the tank through the rotor and back to thetank, a conduit, the said rotor and liquid also operating to create asuction in the conduit, a Water p ump operating to withdraw water ofcondensation from the tank, and means operating automatically to causethe rotor to increase the pressure upon the liquid supplied to the saidWater pump.

12. A closed tank for receiving air and liquid, a rotor operating tocirculate the liquid from the tank through the rotor and back to thetank, a conduit, the said rotor and liquid also operating to create asuction in the conduit, a centrifugal pump operating to constantlyWithdraw Water of condensation from the tank, and means operatingautomatically to cause the rotor to increase the pressure upon theliquid supplied to the said Water pump.

13. A closed tank for receiving air and liquid, a rotor operating tocirculate the liquid from the tank through the rotor and back to thetank, a conduit, the said rotor and liquid operating to create aAsuction in the conduit, a water pump having constant communication withthe tank and operating to Withdraw Water of condensation therefrom, saidtank having a discharge opening for the separated air and gases in thetank, and means influenced by the height of the liquid in the tank forcontrolling the lastsaid discharge opening tocause the rotor to increasethe pressure upon the liquid in the tank supplied to the said waterpump.

In testimony whereof I have signed my name to this specification, onthis 5th day of G5 December, A. D. 1921.

BENJAMIN SKIDMORE, Jn.

